128756749920 has 288 divisors, whose sum is σ = 424821565728. Its totient is φ = 32767967232.

The previous prime is 128756749909. The next prime is 128756749963. The reversal of 128756749920 is 29947657821.

It is a super-2 number, since 2×128756749920² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (60).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 34825512 + ... + 34829208.

It is an arithmetic number, because the mean of its divisors is an integer number (1475074881).

Almost surely, 2^128756749920 is an apocalyptic number.

128756749920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 128756749920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (212410782864).

128756749920 is an abundant number, since it is smaller than the sum of its proper divisors (296064815808).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

128756749920 is a wasteful number, since it uses less digits than its factorization.

128756749920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3842 (or 3797 counting only the distinct ones).

The product of its (nonzero) digits is 15240960, while the sum is 60.

The spelling of 128756749920 in words is "one hundred twenty-eight billion, seven hundred fifty-six million, seven hundred forty-nine thousand, nine hundred twenty".